Liquid crystal alignment by polyhedral oligomeric silsesquioxane (POSS)-polyimide nanocomposites

被引：22

作者：

Liu, Han-Shiang ^{[1
]}

Jeng, Shie-Chang ^{[2
]}

机构：

[1] Natl Chiao Tung Univ, Inst Photon Syst, Tainan 711, Taiwan

[2] Natl Chiao Tung Univ, Inst Imaging & Biomed Photon, Tainan 711, Taiwan

来源：

OPTICAL MATERIALS | 2013年 / 35卷 / 07期

关键词：

Liquid crystal alignment; Nanocomposites; POSS-polyimide; No-bias OCB LCDs; SURFACE FREE-ENERGY; PRETILT ANGLE; SIDE-CHAIN; NANOSTRUCTURED SURFACES; POLYIMIDE SURFACES; DISPLAYS; DEVICES; CELLS; TILT;

D O I：

10.1016/j.optmat.2013.02.011

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Polyimide (PI) films are widely used in the liquid crystal display (LCD) industry to align liquid crystal (LC) molecules in a specific orientation with a pretilt angle 0(p) on the PI alignment films. It was observed that physical dispersion of polyhedral oligomeric silsesquioxane (POSS) nanoparticles in commercial homogenous PIs decreases the surface energy of the PI alignment films and generates a controllable 0(p) in the range 0 degrees < 0(p) < 90 degrees, which is not easily achieved by complicate PI synthesis. Characteristics of POSS-PI nanocomposites were studied to investigate the influence of FOSS nanoparticles on PIs. Increased absorption in the infrared spectra and decreased decomposition temperature and glass transition temperature with POSS doped concentration in PI were observed due to the increase in free volume of POSS-PI nanocomposites. Such nanoscale hybridization suggests a novel approach to tune the properties of PIs through modification of molecular interaction. A fast response no-bias optically-compensated bend (OCB) LCD with a pretilt angle of 68 degrees was also demonstrated in this work. (C) 2013 Elsevier B.V. All rights reserved.

引用

页码：1418 / 1421

页数：4

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